The present invention relates to a device and capsule system for preparing a food liquid from a food substance contained in a receptacle by passing water through the substance using centrifugal forces.
It is known to prepare beverages wherein a mixture consisting of brewed coffee and coffee powder is separated with centrifugal forces. Such a mixture is obtained by bringing hot water and coffee powder together for a defined time. The water is then forced through a screen, on which screen powder material is present.
Existing systems consist of placing the coffee powder in a receptacle which is usually a non-removable part of a machine such as in EP 0367 600B1. Such devices have many disadvantages. Firstly, the coffee powder must be properly dosed manually in the receptacle. Secondly, the centrifuged coffee waste becomes dry and it must be removed by scraping the surface of the receptacle. As a result, the coffee preparation requires a lot of manual handling and is so very time consuming. Usually coffee freshness can also vary a lot and this can impact on the cup quality because coffee comes generally from bulk package or coffee is ground from beans in the receptacle itself.
Also, depending on the manual dosage of coffee and the brewing conditions (e.g., centrifugal speed, receptacle size) the cup quality can vary a lot.
Therefore, these systems have never reached an important commercial success.
In German patent application DE 102005007852, the machine comprises a removable holder into which an open cup-shaped part of the receptacle is placed; the other part or lid being attached to a driving axis of the machine. However, a disadvantage is the intensive manual handling. Another disadvantage is the difficulty to control quality of the coffee due to a lack of control for the dosing of the powder and a lack of control of the freshness of the coffee powder.
Other devices for brewing coffee by centrifuge forces are described in WO 2006/112691; FR2624364; EP0367600; GB2253336; FR2686007; EP0749713; DE4240429; EP0651963; FR2726988; DE4439252; EP0367600; FR2132310; FR2513106; FR2487661; DE3529053; FR2535597; WO2007/041954; DE3529204; DE3719962; FR2685186; DE3241606 and U.S. Pat. No. 4,545,296.
In particular, EP0651963 relates to a centrifugal cell comprising an elastic joint placed at the junction between the drum and the lid of the cell. The elastic joint provides both filtering and control of an operating pressure in the cell, thereby improving coffee cream. The cell is not an airtight container and used coffee must be removed and new coffee must be refilled in the cell for each new brewing cycle. The pressure is difficult to control by such elastic means and the pressure cannot be easily varied depending on the type of beverage to be produced.
BE894031 relates to a centrifugal brewing system comprising a filter capsule which is not sealed but is covered by filter paper.
Therefore, there is a need for proposing a solution which provides a better control of the extraction parameters (e.g., pressure, flow rate, extraction time, etc.) and, consequently, which improves the quality of the delivered food liquid.
At the same time, there is a need for a way of preparing a food liquid which is more convenient and simpler compared to the prior art centrifugal coffee preparation methods and which provides, at the same time, a better in-cup quality by controlling important attributes such as freshness and accurate dosage of the substance.
In particular, there is a need for a system which enables to provide a sufficient interaction time between hot water and the substance to be brewed and controlling the release of the brewed liquid, therefore improving important quality attributes such as, for coffee beverages, the coffee concentration and cream or foam.